Hypodermic syringe



May 24, 1938. F. c. MONTUORI 2,118,221

HYPODERMIC SYRINGE Filed NOV. 14, 1955 Fig.4 Fig. 5 Fig.6

INVENTOR Felix C. Moniuorz' Patented May 24, 1938 UNITED STATES PATENT OFFICE HYPODERMIC SYRINGE Application November 14, 1935, Serial No. 49,675

Claims.

My invention relates to the cartridge holding type of hypodermic syringes and is more particularly concerned with improvements in a modification thereof, which affords increased con- Venience of manipulation for the practitioner. Certain disadvantages manifest themselves in present-day syringes of the cartridge holding type, chief among which are the difiiculty in quickly removing the cartridge from the syringe after completion of the injection, and in inserting or removing the cartridge into and from the body of the barrel of the syringe without breakage occurring to the plunger end of the cartridge which faces the coil spring actuated lock which in turn is attached to the barrel and which serves to securely and accurately hold the cartridge in said body subsequent to insertion.

My invention is intended to remedy these disadvantages by improvements as well as other conveniences which are novel with this type of syringe and will appear hereinafter from the drawing which exemplifies them.

One of the principal features of my invention consists in a system of two leaf springs which is located within the body of the barrel of the syringe, and opposite to the opening of the barrel through which the cartridge is inserted or removed. The leaf springs function, the one to retain the coil spring actuated lock in the syringe head against the action of the coil which normally tends to project the lock outward from the head, whereby insertion and removal of the cartridge into and from the barrel of the syringe is facilitated; and the other to impart a jerking outward movement to the cartridge when the lock in the syringe head is Withdrawn into the head.

I have suggested in my Patent No. 1,757,809, issued May 6, 1930, a syringe which serves the purpose, among others, of easy manipulation in inserting and removing the cartridge into and from the barrel, by means of a single leaf spring which operates upon the cartridge and the lock respectively; this spring functions in both respects from the outer portion of the body of the barrel, and near the plunger end of the cartridge.

The present device is a distinct improvement thereover in that it brings out to fullest advantage the benefits of easy manipulation of the syringe in inserting and removing the cartridge which a leaf spring structure can afford.

The accompanying drawing illustrates my invention as follows:

Figure 1 is a top plan of the entire syringe.

Figure 2 is a side sectional view of the syringe in Fig. 1, along the line A A, showing the cartridge in place in the syringe and the piston ready to enter into the cartridge.

Figure 3 is a similar view partly in section, showing the cartridge in the position which it primarily takes either in being inserted into the syringe or in being ejected therefrom.

Figure 4 is a vertical enlarged section through the slidable hollow sleeve 8.

Figure 5 is a front view of the sleeve in Fig. 4.

Figure 6 is a cross sectional view on line B B of Fig. 3 with the coil spring removed for claritys sake.

Referring to the drawing, l is the hollow barrel of the syringe, 2 is the cartridge, 3 is the lower portion of the barrel adapted to receive the discharge end of the cartridge, 4 is the tubular discharge needle, 5 is the plunger head of the barrel, 6 is a removable cap through which passes the plunger rod 1, 8 is a lock in the form of a hollow sleeve, 9 is a coil spring which tends to force the sleeve 8 away from the cap 6, the cap assembly being detachable from the barrel by means of the threads 90.. p

The inner needle end of the barrel I has the retaining seat Ill upon which the discharge end of the cartridge 2 rests after insertion through the opening I I The lock consists in a slidable hollow sleeve 8 which in the absence of an arresting means is projected outward from the head 5 by the action of the coil spring 9, as is seen from Fig. 2. The outer portion of the sleeve 8 is designed to encompass the plunger end l2 of the cartridge 2 to firmly hold the latter in the barrel I sothat the piston end l3 of the plunger rod 1 may push the slidable plug M of the cartridge 2 to eject medicament through needle 4. This function of the lock is fully obvious from Fig. 2.

On the other hand, Fig. 3 illustrates the sleeve 8 after being withdrawn inwardly into the head 5, through an outward movement of the plunger rod 1, whereby the coil spring 9 is compressed. As will be noted, the piston end of the plunger rod l3 rests against the seat 22 when the plunger is withdrawn into the head with the result that the sleeve 8 is forced against the coil spring 9. As soon as the sleeve is drawn into the head, the leaf spring operates, as seen in Fig. 3, to arrest the sleeve 8 against the action of coil spring 9 thus insuring a free insertion or removal of the cartridge 2 into and from the barrel l.

Upon insertion the cartridge 2 presses the leaf spring l5 downward, thus causing its compression and the consequent release and locking action of the sleeve 8 through expansion of the coil spring 9. Upon freeing the cartridge from the locking action of the sleeve through an outward movement of the plunger rod 1, the leaf spring l5 again resumes its position and arrests the forward movement of the sleeve 8. At the same time, leaf spring l6 forces the cartridge 2 out of the barrel, as is readily apparent from Fig. 3. The automatic arrest of the lock relieves the operator, during insertion or removal of the cartridge, from the burden of preventing an uncontrolled and sudden outward movement of the sleeve from the head 5, which would damage the plunger end of the cartridge 2.

The working of leaf spring IS in combination with the sleeve 8 appears best from a study of Figures 2 to 6. The sleeve 8 is provided with a guideway or channel I1 cut through the entire length of the collar l8 and the seat l9, as well as through the entire width of the collar, but not the entire width of the seat, whereby it leaves the bridge 20. The leaf spring [5 extends into the guideway or channel I! and when the sleeve 8 is drawn into the head by actuating the plunger l3, this spring in uncompressed position rests against the bridge 20, thus retaining the sleeve 8 within the head 5, as shown in Fig. 3. Upon inserting the cartridge 2 into the barrel I the leaf spring I5 is compressed, thus releasing the sleeve 8 which slides out of the head in locking engagement with the plunger end of the cartridge, as is apparent from Figure 2. The guideway or channel l 7 offers ample space to receive the leaf spring I5 when removed from its operative position against the bridge 20 upon insertion of the cartridge.

Upon detaching the cap 6 from the barrel I, a cross section through the latter along line B B" of Fig. 3 appears as shown in Fig. 6, with the coil spring 9 removed for claritys sake. I is the barrel of the syringe provided with the indentation 2|, which latter is in alignment with the leaf spring I 5 and thereby brings the guideway or channel I! in alignment position with the said leaf spring, as appears from Figures 2 and 3. The entire arrangement serves the purpose of facilitating an insertion of the sleeve 8 into the barrel With the resulting proper relation of guideway or channel I! and leaf spring l5.

What I claim is:

1. A hypodermic syringe comprising a tubular body having a longitudinal aperture for insertion of a cartridge, removable means arranged at the plunger end adapted to engage with and retain the cartridge in the body, and resilient means anchored within said body and fastened intermediate its ends therein and adapted automatically to eject the cartridge when said movable retaining means is rendered inoperative and to hold the latter in inoperative position until released.

2. A hypodermic syringe comprising a tubular body having a longitudinal aperture for insertion of a cartridge, a tubular needle affixed to the discharging end, a spring actuated look at the plunger end to hold the cartridge in the body, a

plunger passing through the lock and adapted to withdraw the lock from engagement with the cartridge when said plunger is withdrawn, and a leaf spring anchored intermediate its ends within the body, one of the said ends adapted to eject 4. A hypodermic syringe having in combination a barrel constructed to receive a cartridge; a tubular needle affixed to the discharging end; and a piston mounted at the other end for operating at the end of the cartridge; means for holding the cartridge in place between the needle and the piston; and means located within the body of the barrel and fastened to the barrel intermediate its ends and adapted to automatically eject the cartridge upon a withdrawal movement of the piston.

5. In a cartridge holding hypodermic syringe the combination of a barrel constructed to receive a cartridge; a tubular needle aflixed to the discharging end; a coil spring actuated lock at the plunger end to hold the cartridge in the barrel; a leaf spring located within the body of the barrel to eject the cartridge upon withdrawal of the spring actuated look into inoperative posi tion; and a further leaf spring to retain said coil spring actuated lock at the plunger end in inoperative position until released by insertion of the cartridge into the barrel.

FELIX C. MON'IUORI. 

